title: Antioxidant defenses in the ground squirrel Citellus citellus. 2. The effect of hibernation.
abstract: In spring and autumn, the ground squirrel Citellus citellus is awake and active but in winter it usually hibernates. Reawakening from hibernation involves intense metabolic activity in the interscapular brown adipose tissue (IBAT). The IBAT of hibernation animals showed significant increases in the activities of superoxide dismutase (both copper-zinc and manganese-containing enzymes), glutathione peroxidase, and in the amount of ascorbate present. Glutathione peroxidase also increased in the liver, as did ascorbate in the plasma. These changes were not merely a consequence of exposure to low environmental temperatures. It is proposed that antioxidant defenses are increased in the IBAT of ground squirrels at the onset of hibernation in order to protect the tissue from reactive oxygen species generated as a result of the intense metabolic activity sustained by this tissue during reawakening.
authors.affiliation: Institute for Biological Research, University of Belgrade, Yugoslavia.
authors.forename: B
authors.initials: B
authors.lastname: Buzadzić
authors.forename: M
authors.initials: M
authors.lastname: Spasić
authors.forename: Z S
authors.initials: ZS
authors.lastname: Saicić
authors.forename: R
authors.initials: R
authors.lastname: Radojicić
authors.forename: V M
authors.initials: VM
authors.lastname: Petrović
authors.forename: B
authors.initials: B
authors.lastname: Halliwell
mesh_terms: D002001:Adipose Tissue, Brown / Q000378:metabolism; D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D001205:Ascorbic Acid / Q000378:metabolism; D005609:Free Radicals; D005979:Glutathione Peroxidase / Q000378:metabolism; D006605:Hibernation / Q000502:physiology*; D008297:Male; D010100:Oxygen / Q000378:metabolism; D012589:Sciuridae / Q000378:metabolism*; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D000975:Antioxidants; D005609:Free Radicals; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D001205:Ascorbic Acid; D010100:Oxygen